Duke Zhou sang to the ninth place. Which zodiac is it? Explain?

Chicken. In the Book of Changes, six represents yin and nine represents yang. It's sunny during the day and cloudy at night. "Singing until nine" means that it will turn from yin to yang. The cock crows and it will be bright the day after tomorrow. In addition, in the zodiac, only the crow of a chicken can be called "crow", and there is a poem that proves that "the crow of a chicken is white all over the world".